Implement for cutting cable sheaths



Nov. 30, 1937. J. B. DOOLITTLE IMPLEMENT FOR CUTTING CABLE SHEATHS Filed Jan. 6, 1957 INVENTOR BY JB. 1700a file ATTORN EY Patented Nov. 30, I937 UNHTED STATES OFFKIE This invention relates to implements which are more particularly adapted to be used in connecticn with lead sheaths of cables. More specifically these implements involve knife memdescribed, may be observed through said portion as the blade is drawn along the cable sheath. This cut-away portion also permits the escape of lead shavings during the cutting opbers by which openings, such as slits, may be erations of the sheath. 5

made in the sheaths of cables. A channel is provided on the end of the shoul- It has been found, in the use of aerial transder E and the knife ll may be adjusted by movmission cables, that sheath breaks, ring cuts, ing it back and forth therein until it is in the fatigue cracks and other minor injuries occur in desired position. The knife has two blades, I2

their lead sheaths and permit the entrance of and I3, which may be of the formation illus- 10 moisture. This causes short-circuiting, groundtrated. The blade I2 is of smaller dimension ing or other damage to the insulated conductors than the blade l3 and is initially used to penecontained in the cable, and it. is necessary, in trate the lead sheath while the blade I3 is suborder to clear this condition, that the cable sequently used to enlarge the cut made by the sheath be opened at the point of injury so that blade 12, as will be presently described. The 15 access may be obtained to withdraw the damaged points of these blades are sharpened so that when portions of the conductors for repair. used to cut a cable sheath they rout the lead Accordingly, it is an object of this invention to in a manner similar to the action of a Wood plane. provide a simple and comparatively inexpensive The knife H has a longitudinal slot I4, provided implement by which an incision may be made in centrally therethrough, and a threaded stud I5, 20 a cable sheath for the purpose outlined above. carried on the end of the shoulder 6, extends This and further objects will be apparent from through the slot. The stud I5 is shown as havthe following description, when considered in ing a wing nut M5 on its threaded extremity which connection with the accompanying drawing, in serves, when screwed down, to provide a clamp- 35 which one embodiment of the invention is illusing action of the knife II to maintain it in any trated. desired position to which it may be moved in the Referring to the drawing, Figure 1 is an elechannel. vation illustrating the operating or sheath en- A guard ll, as more clearly shown in Fig. 5, is gaging face of the improved implement; Fig. 2 provided for the knife l I. This guard is applied is a view showing the implement rotated at an at times when the implement is not in use to 30 angle of 90 degrees from the position shown in prevent injury by cutting. The knife guard has Fig. 1; Fig. 3 is a top view of the implement; Fig. an angular slot l8 which permits it to be slipped e is a view similar to Fig. 3 showing a knife guard in position about the stud l5 and on top of the in position thereon; and Fig. 5 is a perspective knife when the nut I6 is loosened. The tight- 5 view of the knife guard. ening of said nut clamps the guard and knife in This improved implement is preferably made position. The guard is provided with downof a light durable metal such as aluminum, and Wardly extending flanges I9 and 20. When the handle portion thereof is shown at 5 in the the guard is in position the flange l9 abuts and drawing. The handle portion is of such size extends along one edge of the blade l3 and 40 and contour that it may be readily grasped and slightly beyond its point. The other edge of the 40 manipulated. Shoulders 6 and l are formed at blade 53 is protected by an overhand portion of the ends of the handle portion and serve to prothe guard, as more clearly shown in Fig. 4. The S p which d t0 Prevent hands flange 2i) forms a shield over the blade I2. s p Whlle Operatmg These This implement is ordinarily employed to make h0u1ders may be of any,des1re d formatmn; for slits in cable sheaths in a longitudinal direction. 45 instance i f be sugstantlani rectingular The small blade I2 is used initially to penetrate as Shown m Flgs 1 and one 0 the aces. of the sheath and is adjusted to cut the sheath to a each of these shoulders has sheath-engaging d d d th Th d d5 8 d 9 f th grooves formed therein, as illustrated at 8 and 9. eslre 8p e grow? en an 0 e These grooves may be of substantially V-shape Shoulder pormons are lald agamit j t pulled 50 and a portion of One side of the groove 3 is cut along the cable sheath to make an lI'iClSlO-Il of the away In the operation of the improved device length -desired. The implement iS turned. Over the side of the groove having the cut-away porfor the e t Operation and a lar blade 15 tion may be held next to the user so that the drawn along in the incision just described to cutting action of the knife blade. to be presently bevel-cut the sheath. It is preferred to again 55 reverse the implement and use the smaller blade l2 to make the final cut to obtain access to the insulated conductors in the cable. When cut as desired the slit portion of the cable sheath may be pulled apart by pliers or other suitable means to provide sufiicient space through which the damaged portions of the insulated conductors may be withdrawn for repair.

While the arrangements of this invention have been illustrated as embodied in a certain specific form which has been deemed desirable, it will be understood that they are capable of many and widely varied forms without departing from the spirit of the invention as defined in the appended claim.

What is claimed is:

An implement for slitting lead sheaths of cables including a handle portion, shoulder members at the ends of and extending transversely from the axis of the handle to space the handle from the cable sheath, said shoulder members forming stops tending to prevent the slipping of the hand in the operation of the implement, said shoulder members also having alined grooves therein for slidably engaging the cable sheath in the movement of the implement along its surface, and a knife member adjustably mounted on the end of one of the shoulder members for slitting the cable sheath in a longitudinal direction.

JOHN BOULWARE DOOLITTLE. 

